Blowpipe



F. S. AUSTIN May 10, 1932.

BLOWPIPE Filed April 2. 195o 2 Sheets-Shes?l l s @Q hw QN :ab (www Patented May l0, 1932 VUNITED STA-TES PATENTV'oFFIcE FRANCIS S. AUSTIN, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO CARBO-OXYGEN COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION F DELAWARE BLoWrIPE Y Application inea April 2, 1930. serial No. 441,054. I

This invention relates to blowpipes such as are employed for the purpose of cutting metal, and has for its general purpose and object to provide a blowpipe of thisI character which is particularly adapted for the removal of protuberances, such as rivet heads, from metal as well as for lthe removal of seams from billets or other metal masses prior to rolling the same, this seam-removing operation being referred to in the art as scarfing7 or de-seaming. In the operation of deseaming or scariing, itis highly desirable to prevent the cutting oXygen from penetrating any material depth into the mass of the metal and, in the operation of removing protuberances, such as rivet heads, it is also highly desirable to accomplish such removal without any material penetration into the body of the metal from which the protuberance projects.

I accomplish the foregoing general objects in and through the construction and arrangement of parts shown in the accompanying drawings, wherein Fig. 1 represents a side elevation of a cutting torch which may be employed as a means for embodying my invention; Fig. 2 a sectional central view through a blowpipe head and tip embodying my invention, the sectional view including the ends of the pipes connected to the head; Figs. 3, 4 and 5 are'sectional views corresponding respectively to the lines 3-3, 44-4 and 5-'5 of Fig. 2; Fig. 6 a plan view of the valve blockand part of `the tubular handle of the blowpipe; Fig. 7 a sectional detail corresponding to the line 7-7 of Fig. 6; and Fig.v 8

a detail in section through the rear end of the .valve block and showinga modification of the valvev controlling the supply of cutting oxygen.

The blowpipe shown herein is of the same general-type as that illustrated and described in the joint application of myself and Lorn Campbell, J r., filed May 31, 1928, Serial N0. 281,950. which has `resulted in Patent No.

' 1,930,4519,A issued November 3, 1931.

' Describing the various parts by reference characters, 1 designates avalve-block which is provided with a connection 2,for oxygen,

and a connection 3, controlled Aby a valve the handle of which is shown at 4', for combustible gas. The valve block, as is commonin the art, is provided with` a valve operated by a lever 5 for controlling the supplyeof'cutting oxygen througha pipe'6 to thehead. It L is also provided with a passage controlled by a valve 7, for supplying `preheating'oxygen through the pipe 8 to such head; while 9 denotesl a pipe leading from the block for conducting the ycombustible gas to the head. From the valve block, a tubular handle 10 extendsl forwardly, surrounding thek parts of the pipes 6, 9 and 8 adjacent to the block. The forward or delivery ends of the pipes 6, 9 and 8 are secured to the rear end of the head 11 of the ,blowpipa i yAbove the pipe 8, the headis provided with an upwardly and forwardly inclined seat 12, which seat ispierced by a bore 13 extending downwardly and forwardly toward the upper portion of a chamber (to kbe described for therecep'tionl of a screw driver and havf ing, on the rear or underside of said head, a

beveled surface 17b adapted to engage the correspondingly beveledseat 12 at the outer end of thebore 13. This plug is provided with a reduced body portion 16aeXtending from-the head thereof and forming the annular distribut-ing chamber 18,'referred to hereinbefore, with the part 13a ofthe bore 13.V The l body of the plug is p-rovidedwith two externally threaded portions, as 'shown at 21, thereby to provide `an annular chamber 22 within the bore 13. The plug is provided with a central bore, the upper portion 23 of which is of smaller diameter than the lower portion 23a. The upper'end of thebore 23 communicates with the chamber 18by means of ports 24, while-the upper end of the bore 23a communicates withthe chamber 22 by means of ports 25. rIfhe lower end of the bore 23a communicates with a chamber 26 formed in the bottom of the bore 13.

The pipe 8 delivers preheating oxygen into the chamber 18 through a bore 27 in the head 11 and the pipe 9 delivers combustible gas to the chamber 22 by means of a bore 28 in such head. Y. e v Y 29 denotes a reduced internally threaded extension of the bore 14, projecting into the upper endroit this threaded extension and a chamber 3() above said seat. An elongated upwardly inclined bore 31 in the head 11 es" tablishes communication between the cham-V ber 30 and the pipe 6 for cutting oxygen.

f The upwardly extending -bore 14, 29 and 29a-is l.provided `for the reception ofa tip, whichwillnow be described. This tip comprisesgenerallyf an vinner member A `and an outery memberA The inner member has a tapered or frustoeconical lower end A, `a reduced tapered or'rusto-conical intermediate portion A2, and a cylindrical upper portion A3. Projecting from the portion A3 is an externally threaded head A4. At its extreme upper end, the inner tip member isprovided with a beveled surface A5 cooperating with the seat 29a. The cylindrical body A3 is provided with a plurality of longitudinal slots 32 which extend from the lower end thereof nearly to the upper end of such cylindricalV portion. Three such slots are shown, but the number may be varied as desired withoutk departing from my invention. The lower frusto-conical part A isprovided with a plurality ofslots. 33, sixsuch slots beingk shown, though the number also may be varied as del"sired without departing from my invention. The outer member B is shown as {itted to the inner member, asy by swaging, and surroundsthe major portion of the cylindrical part A3 andthe remainder of the innertip member below such cylindrical portion. This arrangement provides an annular chamber134 in th'e head above the'outertip memberand withV whichthe upper ends of the slots 32 communicate. `35 denotes a pair of bores extending from opposite sidesof the chamber 26 to opposite sides of theupp'erend ofthe chamber 34. Thesebores are of restricted cross-sectional -area for the purpose ofminimiZing-any prop- -agation of flamegfrom the chamber 34 into ythe Said bores and into the passages and pipes --therebeyondg and they deliver the mixture of preheating gasesta'ngentially into and at each 'side of the said chamber 34, whereby the gasesare whirled and mixed within said chamber.

The preheating mixture is delivered from 'ftheslotted passages 32 intothe chamber C .formed 'between the outertip memberpand the part A2 of the innertip member, and @thence into the slotted passages 33. f f The chamber 30 is arranged axially .above the central bore 36 in the inner tip member, the central bore being intended to deliver cutting oxygen to the metal which has been preheated by the mixture delivered through the passages 33.

The valve block 1 is shown in detail in Figs. A6, 7 'and 8 and preferably isa casting having the threaded connections 2 and 3 referred to hereinbefore and also valve-controlled passages for delivering the oxygenl and the combustible gas to the pipes 6, 8 and 9.

The oxygen from the connection 3 is delivered into a chamber 40 from which a passage 41 leads to a. chamber 42 having a valve seat 43 at its bottom -arrangedto be closed by a ball valve 44 which is pressed to its seat bya light spring 45,* the lower end of the spring engaging the ball and the upper end of the spring being seatedV in a. cap 46' which is threaded into the top of the chamber. From the chamber 42 a short passage 47 delivers the preheating oxygen to a chamber 48, the supply of oxygen to such chamber being controlled by a valve 49 threaded into the chamber and having a conical end49a cooperating Withthe valve seat at the chamber end of ythe passage 47..l From the chamber 48, the preheating oxygen is delivered through a short port 50 to' a bore which communicates with the pipe 8.

At lthe top of the chamber 40 is a valve seat 51 which is adapted to be closed'by a valve 52 ,within the chamber 40 and having astem 53 extending through a smaller cham ber 54 and through the top of lthe valve block, the escape of the gas around the outer end of the stem being prevented by packing 55` and a locking plug 55a. The upper end of the stem 53 is arranged to be engaged by the lever 5 which has its rear end pivoted between l'ugs 56 projecting from the block.

From-the chamber54, a passage 57 conducts cutting oxygen to the pipe' 6. v

rlhe connection 2 for the combustible gas delivers the said gas to a passage 58 whence it is delivered through a vertical passage 59 to a chamberO, the 'flow of the gas to said .chamber being controlledjby a needle'valve 61 cooperating with a valve seatjl at the chamber end of the passage59, the needle valve being threaded into the outer'end of Vthe chamber 60. From the chamber 60,a passage 62 delivers the combustible gas to the ipe 9.

It should be noted that the cross-sectional area. of the interior of the pipe 6, of the passage 3l, and of the bore 36 are substantially the same, the cross-sectional` area of the bore 36 beingggreatlyenlarged as compared with the bores of blowpipe tips heretofore in common use for. the cutting of metal with oxygen'. This cross-sectionalarea is approxi- Vmately twice the cross-sectional area ofthe y'delivery portions of cuttingoxygen bores in tips having the same preheating capacity as mine and is greatly in excess of the crossfsectional areas of the slots or passages 33 for the preheating mixture. Furthermore, the conduit formed by the bore 86, passage` 31, and

the pipe 6 extends without reduction in cross-` sectional area to the chamber 54, it being noted that the passage 57 is alsoof substantially the same internal diameter as the It follows that, from this construction and arrangement af parts, when the metal shall have been preheated in the ordinary manner by the burning jets delivered from the passages 33 andthe valve 52 shall have been opened, the pressure and velocity of the cutting oxygen at the delivery or operatingend but without penetrating or cutting into theV body of the metal mass with the cutting oxygen, with the result that the billet or other body thus tre-ated can be rolled without the development of cracks or seams therein.

In order to adjustably limitthe opening of the valve 52, thereby to enablemeto .set the valve for any desired pressure and/or velocity of oxygen through the conduit leading to the operating end of the torch, I have provided the valve with a stem 62, which is threaded into the central portion of the body of the valve 52 and which' extends downwardly therefrom, the stem 62 being conveno iently formed as a short screw having a slotted head 62a whereby it may be threaded more or less into the valve 52. Mountedon the stem 62 isa lock nut' 68 which serves to retain the stem 62Yin any position to which it may be adjusted.

When the cutting oxygen is not required, the valve 52 is normally seated, as is the usual practice, by a helical spring 64, the upper end of which bears against the bottom of a hollow plug 65 which ,is threaded in the bottom of the chamber 40. It is evident that, bydepressing the lever 5 in the usual manner, the valve 52 will be opened a distance depending upon the adjustment of the screw 62, the amount of such opening being limited by the engagement of the head of the screw with the interior of the head of the plug 65; also that the extent of opening may be varied by adjustment of the screw 62.

In Fig. 8 there is shown a modification of my invention, wherein the valve 52a is provided'with a short lowerstem 66 serving to center the spring 64, but which vdoes not conv stitute 4a l.stop to limit the opening movement of the valve. I-Ioweveigthe extent of opening of the valve 52a' in this `case is con-y trolled by varying the extent of throw which may be imparted to the valve by the lever 5. For this purpose, the part of the lever immediately above the stem 53 is provided with an internally threaded bore 67, in the lower part of which there is threaded a plug 68 having an upwardly convex bottom 68a andy having inthe top a slot 68bfor the reception of a screw driver. By rotating the plug 68 in the appropriate direction, the distance which the lever 5 must be moved before u nseating the valve k52may be varied as desired; and the plug may-be lockedfin the position to which it is adjusted by means of a locking plug 69 threaded into the topnof they bore 67 andalso providedwith a slot 69"l for the reception of a screw driver. As is welll known, the throw of the lever 5 is limited'by its engagementwith the handle casing 10; and the variation of the position of the plug 68 in the lever 5 will effect a corresponding variation in the extent of opening of the valve 52EL when the fro-nt ofthe lever engages such handle casing. kIn both forms of my invention, means are provided for adjustably limitingthe extent of opening ofthe cutting-oxygen 'supply' valve through the operation of the leverv 5. Furthermore, while I have shown and described my invention as embodied in a particularconstruction of blowpipe head, valve block, and tip, it will be obvious thatvother forms and constructions of theaforementioned parts may be employed without departingjfrom the spirit ofY my invention.

Having thus described my invention, what Iclaimis:

l. A blowpipe'comprising in combination a tip having a bore for cutting oxygen and passages for deliveringa mixture of preheat-` ing gases to thedelivery end of said tip adjacent to the said bore, a'hea'duto which the said tip issecured, a passage kfor cutting oxygen in'said head, a pipe connected with said head for supplying cutting oxygen tok said passage, a valve for controlling the supply ,of cutting oxygen through said pipe, the

conduit formed by said! pipe, passage and bore being unobstructed and of substantially the same cross sectional' area throughout its length' and being of materiallyy greater cross sectional area than the cross sectional areas of the said passages, and means for adjustably limiting the vopenin'gmovement of the said valveythereby tovary the' pressure and velocity' of the voxygen delivered into said conduit. y

2. A blowpipe comprising in combination a tip having avbore for kvcutting oxygen and passages for kdelivering a `mixtureof preheating gases to the Vdelivery end o'fsaid tip adjacent lto the said bore,.a head .to which the `said `tip is secured, fa conduit including said bore, a valve for controlling the s upply of cutting oxygenV through said conduit, the

conduit being unobstructed and of substan.

tiallyV the ksame cross sectional area throughout its length from the delivery end of said bore to said valve and being of materially greater cross sectional Yarea than the cross sectional areas of the said passages, and means for adjustably limiting the opening movement of the said valve, thereby to vary the pressure and velocity of the oxygen delivered into said conduit. Y y Y 3. A blowpipe comprising in combination a-,tip having arbore for cutting oxygen and passages for delivering a mixture of preheating gases to the delivery end of said tip and adjacent to the said bore, a head to which the said tip is secured, a conduit including the said bore for cutting oxygen, and a valve controlling the supply ofoxygen to said bore, the said conduit being of substantially the same cross sectional area throughout its length from the delivery end of said tip to said valve and being of materially greater cross sectional area than the cross sectional areas of said passages. f

4. A blowpipe comprising in combination a tip having a bore for cutting oxygen and passages for delivering a mixture ofpreheat- Ying. gases to the delivery end of said tip and adjacent tothe said borne, a head to which the d said tip is secured, a conduit including the said bore for supplying cutting oxygenthereto, lthe said con'duit being of substantially the same cross sectional area throughout its length and being of materially greater cross sectional Varea than the cross sectional areas of the said passages, a valve for admitting cutting oxygen to said conduit, andv means for variably limiting the. extent of opening of thesaid valve.

5. Ablowpipe comprising in combination ya tip having a bore for cutting oxygen and means for deliveringa mixture oipreheating gases to the delivery end of said tip 'adjacent to the said bore, a head to which thev said tip is secured, `a conduit including the said bore for cutting oxygen, a valve block having a chamber therein with which the receiving 'end of said conduit communicates, t-he said chamber having aVV valve seat at the bottom thereof and a chamber extending from and below said seat, a valve in the second chamber and cooperating with said seat, means for supplying oxygen to the chamber below the said seat, a spring in the second chamber engaging the valveyand tending to hold the sameto its seat, the said valve having a stem extending Ythrough the Virst chamber and through the valve block, means on the valve block adapted to depress the stem thereby toV unseat the valve', andan adjustable stop secured to and extending from the valve and adaptedto engage the bottom of the second chamber thereby to variably limit the opening of the valve by the said means.

6. A blowpipe comprising in combination a tip having a boreyfor cutting oxygen and means for delivering a mixture of preheating gases to thedelivery end of said tip adjacent to the said bore, a head in which said tip is mounted, a conduit including the said bore for cutting oxygen, a valve block having a chamber therein with which the receiving end of said conduit communicates, the said chamber havinga valve seat at the bottom thereof, and achamber extending from and below said seat, a valve in the second chamber and cooperating with said seat, means for supplying oxygen'to the chamber beneath the said valve, the said valve having a stem extendingthrough the iirst chamber and through the valve block, a lever pivotally mounted on the valve block and extending across the projecting end of thestem and adaptedl to depress the latter thereby to unseat the valve, a screw threaded into the valve and extending into the second chamber, means for securing the said screw in adjusted position, a cap closing the bottomy of suchsecond chamber, and a spring withinthe second chamber and bearing at onev end against the cap and at its opposite end against the said valve and tending to seat the latterl V7. A blowpipe comprising in combination a tip having a bore for cutting oxygen and means fordelivering a mixture of preheating gases to the delivery end of said tip adjacent to the said bore, a head in which said tip is mounted, a conduit, including the said bore, for cutting oxygen, a' valve block having a chamber therein with which the receiv- "the valveto its seat, theusaid valve having a stem extending throughthe first chamber and through thevalve block, means on the valve block adapted to depress the stem'thereby to unseat the valve,` a screw adjustably vconnected to the valve and extending into the second chamber, and means'for securing the said screw in adjusted position.

8. vA blowpipe comprising in combination a tip having a bore for cutting oxygen and means for delivering a mixture of preheating gases to the delivery end of said tip adjacent to the said bore, a head to which thesaid tip Vis secured, a conduit including the said bore for cutting oxygen, the said conduit being of substantially the same cross sectional area throughout its length, a valve block having a chamber therein'with which the receiving end of said conduit communicates, the said chamber having a valve seat at the bottom thereof, and a chamber extending from and below said seat, a valve in the second chamber and cooperating with said seat, means for supplying oxygen to the chamber beneath the said valve, a spring in the second chamber Y engaging the bottom of the valve and tending to hold the same to its seat, the said valve having a stem extending through the first chamber and through the valve block, a lever piv-l otally mounted on the valve block and eX- tending across the projecting end of the stem and adapted to depress the latter thereby to unseat the valve, and means limiting the movement of the lever in a direction to open the valve.

In testimony Whereof5 I hereunto aix my signature.

FRANCIS S. AUSTIN. 

